package com.mycompany.mvc.utils;

import java.security.MessageDigest;

import static com.alibaba.rocketmq.shade.io.netty.util.internal.StringUtil.byteToHexString;

/**
 * Created by Jintao_Ma on 2017/9/13.
 */
public class SecurityUtil {

    /**  对字符串进行MD5加密     */
    public static String encodeByMD5(String originString){
        if (originString != null){
            try{
                //创建具有指定算法名称的信息摘要
                MessageDigest md = MessageDigest.getInstance("MD5");
                //使用指定的字节数组对摘要进行最后更新，然后完成摘要计算
                byte[] results = md.digest(originString.getBytes());
                //将得到的字节数组变成字符串返回
                String resultString = byteArrayToHexString(results);
                return resultString.toUpperCase();
            } catch(Exception ex){
                ex.printStackTrace();
            }
        }
        return null;
    }

    /**
     * 转换字节数组为十六进制字符串
     * @param     字节数组
     * @return    十六进制字符串
     */
    public static String byteArrayToHexString(byte[] b){
        StringBuffer resultSb = new StringBuffer();
        for (int i = 0; i < b.length; i++){
            resultSb.append(byteToHexString(b[i]));
        }
        return resultSb.toString();
    }
}
